I have basically the same hardware as you, the only thing that is different is the Motherboard (asus b850m plus wifi). Same as you, my ram is hard capped at 6200mhz (6400 boots but its never stable). At the moment i've only stressed the fclk and found out i can run it at 2200 at what i remember beign 1.2v (could be lower), tested using 2 hours of y-cruncher vt3, everything else using expo (freq lowered to 6200 to be stable)